Underground conduit



SPt- 4 1945- F. w. GAY

UNDERGROUND CONDUIT 4 Sheets-Sheet 1 Filed Sept. l, 1942 1 N VENTOR @5%swt 4, 1945 F. w. GAY

UNDERGROUND CONDUIT Filed Sept. 1, 1942 4 Sheets-Sheet 2 Sept. 4, 1945.F, w, GAY 2,384,246

UNDERGROUND CONDUIT Filed Sept. l, 1942 4 Sheets-Sheet 3 M E vmINVENTOR.

BY Eager .6725,

Sept. 4, 1945. F. w. GAY 2,384,246

UNDERGROUND CONDUIT Filed Sept. l, 1942 4 Sheets-Sheet 4 INVENTOR. fa'ef $1 f f ff Patented Sept. 4, 1945 UNITED STATES PATENT OFFICEUNDERGROUND CONDUIT Frazer W. Gay, Mctuchen, N. J.

Application September 1, 1942, Serial No. 456,909

9 Claims.

This inventionrela-tes to an underground conduit adaptedto carry fluidunder high pressure.

Pursuant to this invention it is proposed to bore out said conduit inearth or rock and to shape the Y A conduit according to this inventioncan read- A ily be adapted to carry the duid piston in a Diesel PatentNo. 1,846,389', dated February 23', 1932, or in my United States patentapplication Ser. No. 483,363, filed April 16, 1943.

Pressures upon a conduit surface may vary from a relatively great value'at the inner or working end to a. relatively low value at the outer end.

At the inner or high pressure end of the conduit, I propose to makeconcrete cylinder walls thick, so that the relatively small internalsurface of the conduit is adapted to support a relatively great per unitfluid pressure, and the thick wall will transmit this pressure to arelatively great area of earth (n times the area of an internal wallsurface, n meaning any given or selected number of times) which supportsthe pressures at a much lower per unit value (l/n). As

the maximum per unit pressure decreases along 10 Dump such as describedin my United States side of a crack, so that the high pressure fluidacts as a wedge which tends to continuously drive deeper and deeper intothe crack, and consequently leakage tends to progressively increase.

According to the instant invention I propose to open up cracks whereflat or plane surfaces of the conduit intersect, and, since the pressureon any flat surface is everywhere parallel and perpendicular to theplane thereof, the rock adjacent each flat surface will only be undercompression, and there will be no tendency to development of cracks insuch surfaces. However, since the pressures on adjacent angularlyrelated flat surfaces will act to widen any crack intentionally producedwhere said fiat surfaces meet or intersect, these cracks are sealed toprevent fluid leakage.

I propose to effectively drain to the surface of the earth all cracksintentionally produced between adjacent angularly related flat surfacesby connecting. said cracks by a plurality of ducts increasing in size asthey approach the surface of the earth, whereby any liquid orgas leakingpast the seals into the cracks, and between opposed surfaces of thelatter, loses most of its pressure, and consequently there issubstantially no increase in the adjacent earth pressure caused byleaking fiuid. In constructions where the con- *Y duit is carryingliquid only, the sealing means rock is substantially the samel as theper unit pres- 1 A- in rock are used to carry fluid at a pressure muchgreater than-the pressure prevailing in the rock due to its overburden,that cracks will develop in the passage or conduit walls, by reason ofthe compression of the earth material adjacent to the conduit passage,and consequently the cylindrical bore becomes enlarged and the rockstructure,

y although in compression radially, is put under tensioncrcumferentially. Fluid contained in the conduit under high pressurewill enter said cracks and compress the rock circumferentially each,mediate crack, said rods being doyetailed into each other or keyedtogether in order'to permit some longitudinal movement betweensectionsthereof without leakage where thus Means are provided for holding therods, Sposi-- tion, and pressed'securely throughout their 'entire lengthagainst the crack` to be sealed. i

Portions of the high pressure end of the main conduit which containgases are sealed oil' at the fabricated drainage cracks by interposingbetween the interior thereof and said cracks small hydraulic sealconduits which are split into two halves. cured to one of the angularlyrelated flat main conduit surfaces bordering a crack and the other halfthereof is secured to the other of said flat surfaces, in such mannerthat the split on one side of a seal conduit constitutes a crack betweensaid angularly related flat surfaces, and the split on the other side ofsaid seal conduit opens into or communicates with the externalfabricated drainage crack. These small hydraulic seal conduits, whichare applied at all One half of such seal conduit is sel main .drainagecracks in a large conduit carrying gas, is everywhere subjected to aninternal hydraulic pressure considerably exceeding the g'as pressureexisting anywhere within said large conduit or portion thereof carryinga body of gas. The two splits in the high pressure hydraulic sealconduits are sealed in the same manner as are the drainage cracksleading from the portions of the main conduit adapted to carry liquid`There will be a small leakage valong the splits of the seal conduits onone side into the main'or gas filled conduit and on the other side intothe outgoing fabricated earth crack, but at no point will it be possiblefor the high pressure gas contained in the main conduit to escape intoand through the thus sealed drainage crack.

It is an object of this invention to form underground ducts or conduitsbounded by a plurality of plane flat surfaces angularly related, wherebyall internal pressures are parallel and perpendicular to said surfaces,and there is no tendency for any such surface per se to develop cracks.p

` It is a further object to fabricate or leave cracks where adjacentangularly related conduit surfaces join and to seal said cracks againstleakage from said conduit interior, wherebythe amount of liquid leakingthrough said fabricate cracks is held to a minimum value.

. It is a further object of the present invention to drain saidfabricated cracks to the surface of the earth, whereby the pressuredeveloped by fluids leaking through said cracks can never greatly exceedthe head of water existing above said cracks up to the surface of theearth above.

It is a further object to support the sealing l means comprising rods,or other sealing devices along and in closed relation to said fabricatedcracks, and to provide means whereby said sealing means is securelypressed against said cracks.

It is a further object of the present. invention to provide a hydraulicseal at said fabricated cracks at points where the main conduit isdesigned to support gas pressure; said seal comprising a relativelysmall auxiliary or seal conduit running along and opposed to the mouthof the crack between adjacent angularly related plane surfaces of saidmain conduit. The crack between said plane surfaces including the crack`in between parts of said relatively small auxiliary seal conduit.Hydraulic pressure is maintained at all times in said relatively smallseal conduit having a value greater than the corresponding pneumaticpressure in said gas carrying part of the main conduit, whereby sealingliquid will always leak from said small .auxiliary seal conduit intosaid main conduit; and gas from said main conduit may never leak outagainst the higher hydraulic pressure into said auxiliary seal conduit.Where pressures are low and main conduit surfaces are small, only onecrack may be required in said small auxiliary seal conduit; but wherethe flat surfaces of the main conduit are large, or pressures in saidmain conduit are great, the external fabricated crack may be expected toopen up to such an extent that the material of the small seal conduitwould vbe strained. In such cases, it is an object of this invention toplace two slits in said small seal conduit, one to communicate with themain conduit interior, and the other to open into the exteriorfabricated drainage crack.

It is a further object of this invention tok provide an auxiliarysealing duct means in extension along an earth crack leading outwardlyfrom a gas carrying underground conduit, said sealing Aduct being formedto provide crack-like communication between its interior and the conduitinterior and opposite crack-like communication `into said main conduitand said leakage is held to a minimum value.

Other objects of this invention not at this time more particularlyenumerated will be clearly `understood from the following description ofsame. The invention is clearly illustrated in the accompanying drawings,in which- Fig. 1 .is a sectional view of an underground -conduitconstructed according to, this invention.

Fig.r 2 is a plan view showing the structure between the high pressureend of the conduit and the surrounding rock.

Fig. 3 is an enlarged vertical cross-sectional view, taken on line C--Cin Fig. 1.

Fig. 4 is a further enlarged sectional view of one of the sealing meansshown in Fig. 3.

Fig. 5 is Aan enlarged longitudinal cross sectional view of adjoinedseal ,blocks shown in Fig. 3.

Fig. 6 is a cross sectional view of a sealing means between angularlyrelated flat surfaces of the high pressure endf of the conduit.

Fig. 7 is a cross sectional View of a gas seal means for use at a closedextremity of the high s'pondingV parts. v

Referring to the drawings, Fig. 1 shows the application of a conduitembodying the principles of the present invention to a Humphrey pump.'I'he working or pump end section I3 of the conduit is enlarged and isthat portion thereof which is subject to the greatest fluid pressure.'I'his end of the conduit is furthermore nearest to the surface of theearth where the natural rock pressure due to overburden diminishesrapidly to zero at the surface.

From the end 29 of the conduit I3, 2|, 22 pressure within the samedecreases rapidly as progress is made toward the end at 23 wherepressures are never greatly above the static head of water at thatpoint. Furthermore the natural pressure in the rock increases with depthwhereby the highly compressed rock is quickly able to withstand thegreatly reduced pressure as the play pipe section 22 of the conduit isapproached.

Figure 2 shows the method employed for spreading the high pressureintegrated against the surfaces I5, I5, I5, I5 of the conduit endsection I3, s o that these great pressures at the weak rock surface arespread over the relatively great surfaces 3I, 3|, etc., and are taken upby the-thick backing ofthe continuouswall on the side adjacent conduitextension 2 I The weak earth struc-v assen concentrated pressures withinconduit end action I8 by causing the loads to be borne by the massiveconcrete walls around said conduit end, and the massive structure whichspreads these concentrated loads over a rock structure ot great area, ntimes the area oi' the conduit wall, even though this rock is ofrelatively low per unit strength. Figure l shows that, progressing awayfrom end 28, the massive rock spreader structure is reduced in volume asprogress is made into the earth where the natural pressure in the rockquickly approaches the rapidly decreasing pressure in the conduit I8,2|, 22. Cracks 88, 28, 88, 88, see Fig. 2, are of course extended to therock structure II, II, 8| and enlarge toward the surface to give amplearea for the escape of fluid that may leak out oi' conduit end sectionI8 so that there is no possibility of fluid pressure building up in therock structure 8|, 8|, 8|.

The high-pressure exit chamber opens out through the arched opening 28into the conical guide reducer 2|. Liquid flows from the guide reducer2i into an'd through the rectangular play pipe section 22 of theconduit. A cross-sectional view oi' this play section 22 oi' the conduitis shown in Fig. 3, said section being taken along line C-C in Fig. 1.While the drawings show a rectangular lil play pipe section 22, it is tobe understood that the same may be of any other polygonal shape incross-section. 'I'he low pressure end of said play pipe section 22expands outwardly through the expanding elbow 28.

It will be noted that the entire force on the walls of the working orpump end section I8, on the walls of the reducer 2|, and on the walls ofthe play pipe section 22, is taken by the rock structure of the earth,leaving only the upward force at the end 28 of the working or pump endsection I3 to be otherwise carried. As shown, the upward force iscarried by a weighty head or stopper I8 comprising an enormous mass ofconcrete and gravel. 'I'he main structure of this stopper is reenforcedconcrete, but a great part of the weight thereof is made up by a illlingwhich is preferablyrock and gravel.

The main play pipe section 22 is formed by a plurality of flat walls 18,1li, etc.; and at each corner`where these fiat walls meet there is lefta crack opening into a crevice 12,12, etc. cut out of the rock andforming an outgoing passage. The pressure within the play pipe section22 will cause the cracks to extend as at 81, at locations where thepressure is sufiiciently high. These passages 12, 12, etc., are drainedby the drain pipes 18, 18, etc., so that it is not possible forAhydraulic fluid leaking out of the play pipe section 22 to build up ineach corner. It is proposed to block this duct at frequent intervals sothat hydraulic huid will not flow in these small ducts. the i'iow beingconlined entirely to the central passage. Frequent small openings willbe provided through the bailes 14 so that the pressure on. both sides ofthe baiiies will be substantially equal.

Fig. 4 shows an enlarged section included in the ring R of Fig. 3. Fig.4 shows one sealing block 14 in the corner formed by two Z-bars 1l, 18.These Z-bars each have one of their flanges forming part of the wall ofthe drain passage 12. The other flange of the Z -bar is within thecylinder and at frequent intervals has holes drilled in it toaccommodate the pipes 18, 18, which are welded in place and form guidesfor the springs 18, 18. These springs each press a seal block 14securely into'the corner of the conduit section 22 without regard to thepressure within the latter. Fig. 4 also shows the longitudinal stops 86,86. These stops engage lugs on the seal block 14 (not shown) -whichallow the seal blocks 14 to move a very limited amount longitudinally.

Fig. 5 shows an enlarged'cross section of the sealing key 80 oi Fig. 4,as enclosed by the ring marked N in Fig. 4. 82, 82 are keyways carefullycut in the ends of seal blocks 14, 14 so as to exactly match. The key 88is made to llt in the keyways very closely, and longitudinal stops 83,83 are welded into the keyways to allow the key 80 only a limitedlongitudinal motion. This key 80 seals the hydraulic iiuid which wouldotherwise escape out of the conduit through the crack 84 betweenadjacent sealing blocks 14, 14 and thence directly through the crack atthis point between the fiat walls of conduit section 22.

Fig. 6 shows two fiat walls I5, I5 of the working or'pump end section I8of the conduit and a high pressures outside of the conduit itself. It

is to be understood that this section 22 of the conduit, and othersimilar structures, are lined by a thin steel skin I 24; and in thepreferred form oi' the lining, I elect to place small passages atfrequent intervals between the lining skinand the concrete which draininto the drain passages 12, 12, etc., so that leakage (ii' any) willbreak out into the passages 12 and will not build up destructivepressures in any part of the rock structure. Fig. 3 shows the crackssealed by the sealing blocks 14, 14, etc., and it further shows thesealing blocks protected against fluid friction by the thinanti-friction baliies 1I, 1I, etc., so that the interior of thehydraulic conduit section 22 exposes at all points only fiat or slightlycurved surfaces to the flow ot the water. It will be noted that thebames 1i provide a small auxiliary duct -the cracks between walls I5,

gas seal to prevent gases within the section I8 from leaking through thecracks where the ilat surfaces I5, I5 join. This seal-comprises a smallpassage 90, one corner of which comprises one of of the conduit sectionI3. Diagonally opposite this crack is another crack which communicateswith the drain-A passage 12. The hydraulic pres? sure in the small`passage is maintained always greater than the gas pressure in theconduit section I8 so that the liquid in the passage 90 will always leakoutwards either into said conduit section I8 or into the drain passage12. Seals 14, 14 reduce the now of liquid .out of the passage 90 in thesame manner as the seals 14,

14 in the passage of conduit section 22, as shown in Fig. `4.

The metal structures 98, 94 and 95 constitute the walls of the smallpassage 90 and are arranged to provide access to the seal blocks 14, 14as shown. It will be understood that it is necessary to make provisionsin the head or stopper I8 as shown in Figl l, so that these corners areaccessible. This will of course slightly increase the clearance in theconduit section I3, and the amount of this objectionable clearance willbe kept to a minimum by filling the corner openings with bolted-inblocks.

Fig. 7 shows a gas seal around the topv of con-x rock structurevSI andlThis is very lsimilar tofy the construction shown in Fig. 6. In thiscase duit section Il between the the head or stopper I8.

the high-pressure passage INI vents on the outside where leakage must bedrained and pumpedv away, and on the inside into the conduit section I3.

Fig. 8 shows an expansion joint, as for instance I5 in the interior`.and Fig. 2).

as at Pand Q, in the conduit section 22 (Fig. 1 Steel blocks |22, |22are welded to the skin |20 of the conduit section 22, and the smallcrack p between these steel blocks is vented to the drain 35. Othersmall drains as IS, 30, 39, 39 areshown so as to maintain a relativelylow pressure back of the steel skin |24, |24 which is secured to theouter concrete walls 10, by the welded-on tacks |23, |23, etc. The ap 30is mortised into the corner seal blocks as shown diagrammatically at l0,00 in Fig. 4. The seal flaps' 36 are pressed down bysteel springs l1held in position by steel blocks 30. Steel blocks 38 are welded to theskin |24.

Fig. 9 shows one way to maintain .the necessary excess pressure in thegas seals, as for instance in the seal duct 90 shown in Fig. 6 for thevertical cracks, and in the seal duct |00 shown in Fig. 7 for horizontalcracks. In Fig. 9, |00 represents a motor driving a centrifugal pump|01.

assauts ing' at angles, cracks at said angles, and small ducts arrangedalong-each said crack, each said small duct also having longitudinalcracks and the crack where two sides of said large gashandling conduitintersect also being the crack in the associated small liquid-carryingduct and pressure producing means connectedA to continually maintain aliquid pressure in said small ducts higher than said gas-pressure insaid conduit.

4. A conduit in the earth adapted to carry gas at high pressure;saidvconduit comprising: at sidewals intersecting at angles, cracks atsaid angles and small ducts arranged along each said crack, each saidsmall duct also having longitudinal cracks, and the crack where twosides of said lbs. above the liquid pressure in conduit section' I3 isled by pipes |90, |90, etc., into the vertical etc., into the horizontalseal passages |00. |00, etc.

Many changes could be made in the above construction, and manyapparently widely-different embodiments of this invention could be madewithout departing from the scope thereof. It is intended that all matterpertaining to the above description, or shown in the accompanyingdrawings, be interpreted as illustrative and not in the limiting sense.

What is` claimed is:

1. In a conduit in the earth adapted to carry iluid at relatively highpressure comprising: a

sides, a mechanically strong structure built between each said at sideand the earth and having a relatively greater surface area at its outerearth contacting face, said structure supporting the fluid. pressureinsaid conduit'portion acting on the relatively small' surface of saidconduit ilat sides at relativelv high unit pressure and transmittingsaid pressure to a relatively large earth surface at relatively low unitpressure, and a drained crack along the intersecting edges of adjacentconduit flat sides of said conduit portion, -whereby leakage from saidhigh pressure fluid is drained away at relatively low pressure, andseals along said cracks to reduce fluid leakage from said conduit. Y 2.In.- a conduit in the earth adaptedA to carry fluid at relatively highunit pressure comprising: a portion of said conduit having a pluralityof flat sides, a, mechanically strong structure built between each saidflat side and the earth and having a relatively greater surface area atits outer earth contacting face, said structures supporting the iiuidpressure in said rconduit acting onthe relatively small surface of saidconduit fiat sides at relatively high unit. pressure and transmittingsaid pressure to a relatively large earth surface at relatively low unitpressure, a drained crack along the intersecting edges of adjacentconduit dat sides, whereby leakage from said high pressure conduit isdrained away at relatively low pressure.

3. A conduit in the earth adapted to carry gas at high pressure; saidconduit comprising: :dat sidewalls supported by said earth andintersectseal passages 90, 90, etc., and by pipes |09, |09, 4

.having ilat side walls supportedby said earthand intersecting at anglesso as to provide inf.

. Atervening cracks, drains through the earth along '40 portion of saidconduit having a plurality of fiatA 'said cracks ,toV drain off leakageemitted through said cracks, said drains being of substantialcrosssection'al area so as to maintain the kpressure in said drains .ata relatively low value, blocks snugmasses-interposed between saidsidewalls and the surrounding earth, said side walls and concretemassesintersecting at angles so as to provide intervening cracks, duct meansexteriorly of said conduit contiguous to said cracks adapted to receiveand carry of! leakage emitted throughl said cracks, means to drain saidduct means whereby to prevent pressure buildup therein of said emittedleakage, and hydraulic seals snugly fitted within-the angles of saidside walls to hold leakage through said cracks to a minimum.

[1. A conduit in the earth adapted to transmit fluid at high pressurecomprising a plurality of angularly adjoinedilat side walls, each sidewall comprising a metallic inner face liner having reenforced edgeportions, a, supporting concrete wall body between said liner and theadjacent earth mass, wherebyfV to rigidly back each Yside wall by saidearth mass, juxtaposed reenforced edge portions of'adjoining linersbeing arranged to provide intervening cracks, said earth mass havingdrain means formed therein for communication with said cracksfwhereby toreceive uid f leaking outwardly therethrough from said vconduit, saiddrain means including iiuid venting means, whereby to prevent exertionof excessive fluidpressure within the earth mass, and hydraulic sealmeans snugly thrust into the interior angles of adjoining liners,whereby to reduce leaktermediate opposed edges o! adjoining walls innermetallic liner member having reeni'orced side margins and a concreteouter member backed by said earth whereby to provide unyielding supportfor said liner member, means exteriorly ot the conduit adapted toreceive and ireely drain of! nuid leakage emitted through said cracksfrom the conduit interior. and hydraulic seal means snugly thrust intothe interior angles of adjoining liner members, whereby to reduceleakage from the conduit interior through said cracks.

9. A conduit in the earth adapted to carry iiuid at high pressurecomprising a plurality of ilat walls supported by the surrounding earth,said surrounding earth having cracks along and inextending radiallyoutward along mum earth stress, whereby the within the conduit actingnormal walls tends to open said cracks only changes in pressure ortemperature, a rigid. chanically strong and impermeable lining foreachsaid wall, drains cooperative with said cracks. and hydraulic sealscooperative with the wall joints adapted to reduce leakage therethroughto a minimum.

FRAZER W. GAY.

